The FAA has received reports of two in-flight shutdowns and one aborted take-off on three different Boeing 737NG airplanes powered by CFM56-7B turbofan engines. In all of these cases, the engine rolled back to idle speed and would not accelerate. The investigation revealed that the PS3 pressure line B-nut fitting at the 6 o'clock position had disconnected in two of these events and the PS3 pressure B-nut fitting at the combustion case port location had disconnected in the third event. An operator, involved in one of the IFSD events, completed on-wing torque inspections of the PS3 pressure line fittings of its CFMI CFM56-7B fleet. As a result of these inspections, one engine was found with a loose B-nut fitting at the 6 o'clock location and two engines were found with loose cap fittings at the 6 o'clock location. The two engines with loose caps were on the same airplane. The investigation also initiated PS3 pressure line fitting torque inspections on 10 engines that were on Boeing's flight line. These inspections revealed one engine with a loose B-nut fitting at the 6 o'clock position and one engine with a loose cap fitting at the 6 o'clock position. General Electric and SNECMA also inspected CFM56-7B engines that were in assembly. No loose fittings were found. The investigation to determine the cause of the loose PS3 pressure line fittings continues. Action to insure correct torque of these fittings on current production engines has been initiated by adding a new torque inspection requirement for the PS3 pressure line fittings at the end of the main engine assembly process. However, based on the inspection results indicated above, it has been determined that mandating action on in- service engines to ensure that the PS3 pressure line fittings are correctly torqued is required. \n\nRequirements of This AD \nSince an unsafe condition has been identified that is likely to exist or develop on other engines of the same type design, this AD is being issued to prevent air leakage from incorrectly torqued fittings of the PS3 line, which could result in engine power loss. \n\n\tThis AD requires a one-time, on-wing torque inspection of all the PS3 pressure line fittings to insure correct torque and, if necessary, torquing of those fittings to their correct value within 25 days after the effective date of this AD. \n\nImmediate Adoption of This AD \nSince a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days. \n\nComments Invited \nAlthough this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views,or arguments, as they may desire. Communications should identify the Rules Docket number and be submitted in triplicate to the address specified under the caption "ADDRESSES." All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed. \n\n\tComments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket. \n\n\tCommenters wishing the FAA to acknowledge receipt of their comments submitted in response to this action must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 2001-NE-03-AD." The postcard will be date stamped and returned to the commenter. \n\nRegulatory Impact \nThis proposed rule does not have federalism implications, as defined in Executive Order No. 13132, because it would not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. Accordingly, the FAA has not consulted with state authorities prior to publication of this proposed rule. \n\n\tThe FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES." \n\nList of Subjects in 14 CFR Part 39 \nAir transportation, Aircraft, Aviation safety, Safety. \n\nAdoption of the Amendment \nAccordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows: \n\nPART 39 - AIRWORTHINESS DIRECTIVES \n1. The authority citation for part 39 continues to read as follows: \n\tAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\n§39.13 (Amended) \n2. Section 39.13 is amended byadding the following new airworthiness directive: